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        <li>
            <h2>北京市</h2>
            <ul>
                <li>朝阳区</li>
                <li>海淀区</li>
                <li>昌平区</li>
            </ul>
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            <h2>上海市</h2>
            <ul>
                <li>静安区</li>
                <li>浦东新区</li>
            </ul>
        </li>
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